Process of treating hydrocarbons



Aug. 9, 1932. w M. CROSS- PROCESS OF TREATING HYDROCARBONS Filed 00L 6,1924 s Sheets-Sheet 1 INVENTOR [fa/7% 0'03; 744/ @@@Q 0 o 0 13m a M o oo ATTO EY.

Aug. Q, 1932. w. M. CROSS PROCESS OF TREATING HYDROOARBONS 3Sheets-Sheet 3 Filed Oct.

ATTO EY.

Patented Aug. 9, 1932 WALTER M. CROSS, OF KANSAS CITY, MISSOURI,ASSIGNGR, BY MESHE ASSIGTS,

TO GASOLINE PRODUCTS COMPANY, INC., OF WILMINGTON, DELAWARE, A CORPO-RATION or DELAWARE PROCESS OF TBEATHJ'G H'YDRGGARBQNS Application filedOctober 6, 1324:. Serial No. $11,318.

This invention relates to improvements in a process of treatinghydrocarbons, and refers more particularly toa process usedforconverting-relatively heavy hydrocarbons into lighter hydrocarbonspreferably of a gasoline-like nature.

This application is a continuation in part of aprevious applicationSerial No. 503,335, filed September 26, 1921, which was in turn a truedivisional of an original or parent ap. plication Serial No. 128,839,filed November In the process of this invention the hydrocarbons aretreated in a continuous process as distinguished from an intermittentprocess, thereby not only permitting a fresh supply of hydrocarbon oilto be continuously fed to the apparatus, but also resulting in gettingmore uniform and better results.

In addition to charging an oil to be treated continuously, the convertedproduct was drawn ofi continuously and directed to a stage of reducedpressure where the treated material was distilled with the containedheat of the oil due to the pressure reduction which took place betweenthe conyersion stage and the distillation stage.

Among the advantages of the invention are much increased economy ofoperation, not only in fuel consumption, but also in the quantity of oilthat can be treated at a given time. A further advantage is thatinasmuch as in the continuous process, the temperature can be maintainedsubstantially constant for relatively long periods of time instead ofalternately heating and coolingthe apparatus as is necessaryv inintermittently operated processes, and the life of the apparatus. willbe correspondingly prolonged as there will be much less strain on thestill. Other advantages of the invention will appear to those tubearrangement on an enlarged scale.

Fig. 3 is a plan View, partly diagrammatic and partly in section, of myimproved apparatus.

Fig. i is a transverse sectional view taken on lines 1- 1 of Fig. 3 buton an enlarged scale. f

Referring to Figs. 1 and 2, 1 designates a furnace having the usual firebox'2, above which is located a series of tubes 3, opening at theiropposite ends "into hollow plates 4 and 5. A plurality of bafiie plates6 and 7 are employed in the furnaces for. forcing the hot gases alongsubstantially the entire length of thetubes 3 before passing to thestack 8. Opening into the lower portion is an inlet 9 connected to asource of supply in the manner hereinafter described, and at the upperend of the end plate is an outlet 10 connected by a conduit 11 withconverter tank 12. Leading from this convertor tank is a pair ofdischarge pipes 13 and 14:, the latter ofwhich connects with a reheater15, and the former is connected with the inlet pipe 9. Referring toFigs. 3, 18, 18a, 1822, 180, 18d and 186 represent circulating pumps.19, 19a, 19?), etc., represent the motors to drive the same. 13, 13a,13?), etc., and 11, 11a,,11b, etc., represent the circulation pipes.Disposed at right;

angles to the longitudinal axis of the chamf' ber 12 are a plurality ofbafiie plates 34a, 34b,

340, 34d, 34c; 33 is a main supply pump, and 36 a motor to drive thesame, 37 the intake pump 33 and emptying into the chamber 12.

In the employment of this apparatus, it

is contemplated that the substance .treated will circulate from theconvertor tank 12 freely through the furnace tubes 3 (Fig. 2) of theheating furnaces 1, 1a, 112, etc., and

back into'the convertor tank 12. In order to said pump and 35 is a feedpipe extending from the in a continuous passage, that is, oil introducedat one end of the convertor tank will be circulated through the heatingcoil in the furnace 1, thence back into the convertor through thedischarge line 11 and into the next succeeding coil positioned in thefurnace 1a; through the line 13a, and back to the convertor through theline 11a. The oil circulated in this manner travels continuously fromthe charging line to the discharge line 14. The passage through thevarious pipes is controlledby suitable valves, a cutoff valve 22 is inposition on the pi e 14 for controlling the passage of treate oil fromthe convertor tank 12 to the still 15. Also the pipe 31 is provided witha cutoff valve 32 for controlling the flow of vapor from the convertor12 direct to the condenser 29. A p1pe 28 leading from the still 15 tothe condenser 29 is provided with a check valve 39. The optlet of thecondenser coil 29 is provlded with a valve 40.

In'starting the process, the mtake 37 of the pump 33 is connected with asuitable supply of oil to be treated, Then the pump 33 is started anddriven by the motor 36, pumping the oil into the convertor 12 throughthe intake 35. As soon as suflicient oil is pumped into the apparatus,one third full more or less, the circulating pumps 18, 18a ,18b, etc.,are all started and heat is applied in the furnaces 1, 1a, 16, etc. Nowthe pump 33 1s stopped, and the heat is applled 1n the furnaces 1, 1a,16, etc., until the pressure 1n the apparatus reaches the point that it1ncreas es out of proportion to the temperature, that 1s, when such atemperature is reached that pressure begins to rise without any further1ncrease in temperature, the pressure in this case being that pressuredue to the vapors from the hydrocarbons subjected to the treatment beinggenerated by the heat. Now this reacting temperature is maintained for aperiod of thirty minutes more or less according to the character of theoil used. In any event, the temperature is maintained in the apparatusuntil a substantial amount of conversion products or gasoline-likeproducts is obtained or formed in the oil itself. After this reactingtime has been allowed, the valve 22 is opened andthe pump 33 againstarted so that the discharge of oil through the pipe 14 together withany discharge of vapor is replaced by the oil that is pumped in throughthe intake 35 simultaneously. If the pressure becomes excessive, thevalve 32 is opened.

and some of the vapors are allowed to pass out through the pipe 31 intothe condenser 29 and then discharged. If satisfactory c ondensation andseparation of the condensible vapors from non-condensible vapors'is notaccomplished in the condenser 29 when it is operated at atmosphericpressure, the valve $0 'on the outlet of the condenser is partiallyclosed so that suflicient pressure is built up in the condenser 29 so asto insure satisfactory separation of condensible from non-condensiblevapors in the condenser 29. When suflicient oil has been dischargedthrough the pipe 14 into the still. 15 so asto partially oil, additionalheat will be necessary to effect the desired degree of volatilization.Simultaneously, vapor may also be delivered into the condenser 29through the pipe 31 and valve 32. As previously mentioned, the overheadmaterial withdrawn from vthe conversion stage may consist of bothincondensible and condensible material. The length of the convertorchamber 12 and the number of heating furnaces 1, 1a, 1b,. etc., will bedetermined entirely by the amount of oil that is to be treated in anyone 24-hour period. The oil in this process, after it is started, ispumped in at such a rate that it will remain in the apparatus and besubjected to the reacting temperatures thirty minutes more or less ac-.cording to the time requiredfor producing gasoline or gasoline-likebodies. A pressure of from 100 to 800 pounds may be maintained, thisvarying with conditions.

It is self-evident that the longer the convertor chamber 12 and the morenumerous the furnaces 1, 1a. 1?). etc., the more rapidly oil can bepumped in the apparatus and still allow the necessary reactive time forthe production of the gasoline-like product. In order that the oil maynot circulate by convection backward, bafiie plates 34a, 34b, 34c, 34d,34c, etc., may be placed in the vapor chamber 12 at right angles to itslongitudinal dimensions. A cross section of the convertor chamber 12with baflie plates 34a, etc., is shown in Fig. 4. The height ofthisbaffle plate is ,one-fourth the diameter of the vapor chamber 12. moreor less according to the amount of oil that is being carried in theapparatus during the operation.

The operation of this process provides means for continuous operationand recovery pf gasollne and gasoline-like products durmg the operationof the process. It is well known that if a hydrocarbon oil is beingsubected to a-cracking process or a conversion process, whereby lighthydrocarbons are formed that there are also formed methane and othergases, which cannot be condensed into a liquid at atmospherictemperature. The amount of methane and non-condensible retreat gas thenis proportioned to-the amount of like product that is condensible into aliquid at atmospheric temperature. In the operation of this process,such pressure is produced that gasoline or gasoline-like bodies mayexist inical equilibrium in as great amount as would be the case if thevapor and oil were withdrawn at the same time. Laboratory apparatus,operated in this way, showed conclusively that it during the operationof the process, non-condensible gas was withdrawn, a larger amountof-gas was formed than is the case were it not withdrawn. Also it wasdemonstrated that if the gasoline were removed from the apparatus whilethe process was in operation, that a somewhat larger yield was obtainedthan was the case when-the volatilematerial was removed at the sametime. It was necessary, however, to remove some of the volatile materialas the pressure rose excessively high if it was not done,rprovided. thegasoline waswithdrawn and new oil pumped in during the operation of theapparatus. 3 I

In my copending application Serial No. 667,380, filed Oct. 8, 1923, Ihave set forth and claimed certain of the subject matter describedherein.

I claim as my invention:

1. An improvement in the art of oil conversion for the purpose ofproducing lighter from heavier hydrocarbons, which consists insubjecting the oil in a tube and tank to cracking conditions oftemperature and a pressure controlled to prevent substantialvaporization of the light hydrocarbons, re-

moving vaporous products of conversion from the oil body undergoingcracking to prevent excessive pressure, withdrawing continuously theunvaporized liquid products and distilling therefrom the lighterfractions by reducing the pressure thereon, condensing and collectingthe evolved vapors from the distillation under reduced pressure and thesaid vaporous products of conversion.

2. An improvement in the art of oil conver-' sion for the purpose ofproducing lighter from heavier hydrocarbons, which consists insubjecting the oil in a tube and tank to cracking conditions oftemperature and pressure,

controlled to prevent substantial vaporiza point in the conversion stageto control the pressure in said stage and the liquid products from alowpoint, releasing the pressure on the liquid products whereby the lighterfractions will distill ofi,,condensing and collectingcondensiblematerial from the evolved vapors together with the product removed fromthe high point of the conversion stage.

3. An imprcvementin the art of oil conversion for the purpose ofproducing lighter from heavier hydrocarbons, which consists insubjecting the oil in a tube and tank to cracking conditions oftemperature and pressure, controlled to prevent substantialvaporizationvv ofqthe .light hydrocarbons, removing gaseous productsfrom the oil body undergoing cracking to control the pressure in saidoil body, continuously withdrawing the liquid converted materialandpassing it to a zone of reduced pressure without cooling whereby thelighter fractions will distill off, simultaneously condensing andcollecting the condensible products from the volatile material withdrawnfrom the cracking stage and prevent any substantial portion fromvaporizing at temperatures to which the oil is heated, simultaneouslyandseparately withdrawing gaseous and liquid products from the conversionchamber, passing the liquid cooling whereby the lighter fractions willdistill off," liquefying by condensation condensible products from thematerial removed from the cracking stage together with vapors evolved inthe zone of reduced pressure.

' 5. An improvement in the art of oil conproduct to .avzone of reducedpressure without version for the purpose of producing lighter fromheavier hydrocarbons, which consists in charging oilcontinuously to atube and enlarged conversion chambenin maintaining and subjecting it totemperature and pressure conditions to induce cracking but prevent anysubstantial portion from vaporizing at tem peratures to which the oilisv heated, simultaneously and separately withdrawing gaseous and liquidproducts from the" conversion chamber, passing the liquid product to azone of reduced pressure without cooling whereby the lighter fractionswill distill off, liquefying by condensation condensible products fromthe volatile material withdrawn from "the-conversion.stage and thevapors evolved products under by distillation'of the liquid reducedpressure conditions.

j 6. An improvement in the art of pressure distillation. for the purposeof: producing lighter from heavier hydrocarbons, which consists insubjecting the oil in a tube and prevent excessive pressure on the oilundergoing conversion in the chamber, continuously passing the heatedunvaporized hydrocarbons without cooling to a still and there distillingoff the lighter fractions under reduced pressure conditions, condensingsuch lighter fractions in combination with the lighter fractions removedfrom the initial zone ofconversion.

7. A process of converting heavy hydro-- carbons into lower boilingpoint hydrocarbons consisting in passing the oil continuously through acracking chamber comprising local circulations of relatively smallquantities of oil through heating tubes and returning the same to a bulkof supply, maintaining such a pressure on the hydrocarbons as willprevent any substantial portion thereof vaporizing at temperatures towhich they are subjected in this cracking chamber, passing regulatedquantities of cracked oil in a liquid condition without substantialcooling to a still in which the oil is released to atmospheric pressure,and taking ofi incondensible gases from the cracking chamber to preventexcess rise in pressure.

8. A process Of'CODVGItiIlg heavy hydrocarbons into lower'boiling pointhydrocarbons consisting in passing the oil continuously through acracking chamber comprising local circulations of relatively smallquantities of oil from a bulk supply'maintained in a converter notcompletely filled with oil through heating tubes, returning this heatedoil to the converter, and maintaining such a pressure on thehydrocarbons as will prevent any substantial portion thereof vaporizingat temperatures to which they are subjected in this cracking chamber,passing regulated quantities of cracked oil in a liquid'conditionwithout substantial cooling to a still in which the oilis' released toatmospheric pressure, taking off incondensible gases from the crackingchamber to prevent excess rise in pressure, the pressure in the crackingchamber being maintained by the incondensible gases formed and suchvapors as are vgenerated.

9. A process of converting heavy hydrocarbons into lower boiling pointhydrocar bons, consisting in continuously passing the oil through aheated cracking chamber comprising local circulations of relativelysmall quantities of oil from a bulk supply maintained in a converter notcompletely filled with oil through heating tubes, returning this heatedoil to the converter, and maintaining such a pressure on the oil as willprevent the major portion thereof from vaporizing at temperatures atwhich the oil is heated, while passing through said cracking chamber,causing the oil to pass from said cracking chamher without substantialcooling to a still in which the oil is released to substantiallyatmospheric pressure and taking off incondensible gases from thecracking chamber sufficient to prevent excess rise in pressure.

10. A process of converting heavy hydrocarbons into lower boiling pointhydrocarbons, consisting in passing the oil through heating .units,thence combining the heated oil from said units in a converter chamber,and maintaining sue a pressure on the oil as will prevent the ma orportion thereof from vaporizing at temperatures to which the oil isheated, causing local circulation through the heating units from theconverter chamber, passing the heated oil without substantial cooling toa still in which the oil is released to substantially atmosphericressure, and taking off incondensible gases om the converter chambersufiicient to prevent excess rise in pressure.

11. A process in accordance with claim 7 wherein said heating tubes aresubjected to independent sources of heat.

12. A process in accordance with claim 10 wherein said heating units areindependent from one another..

13. An improvement in the art of oil conversion for the purpose ofproducing lighter from heavier hydrocarbon products, which consist inmaintaining a considerable body of oil undercracking conditions oftemperature and pressure, continuously withdrawing oil from the saidbody and passing the oil without cooling and without intermingling with'a higher temperature inert heating medium to a still into which the oilis released at reduced pressure whereby the lighter fractions arevaporized, removing the resulting vaporized lighter fractions, takingofi condensible and incondensible gases from said body to prevent anexcessive rise in pressure and combining said condensible andincondensible gases with vaporized lighter fractions removed from saidstill and subjecting the combined; gases and vaporized lighter fractionsto cooling to effect condensation.

14. An improvement in the art of oil conversion for the purpose ofproducing lighter from heavier hydrocarbon oil which comprises passingsaid heavier hydrocarbon oil in a relatively small stream through aheating zone, wherein it-is heated to' cracking temperature, thenconducting the oil from said stream after heating to an enlarged body ofoil located outside of said heating zone, maintaining crackingconditions of temperature and pressure on said body, continuouslywithdrawing oil from said body and passing the oil without cooling andwithout interminglingw-ithahigher temperature inert heating medium to astill into which it is released at l a reduced pressure whereby thelighter fractions are vaporized, removing the resulting vaporizedlighter fractions, taking 01f con,- densible and incondensible gasesfrom the cracking stage to prevent excessive rise in pressure andcombining said condensible and incondensible gases with vaporizedlighter fractions removed from said still, and subjecting the combinedgases and vaporized lighter fractions to cooling to effect condensation.

WALTER M. CROSS.

